Anisotropic spin fluctuations in detwinned FeSe
arXiv:1905.08399 · doi:10.1038/s41563-019-0369-5
Abstract
Superconductivity in FeSe emerges from a nematic phase that breaks four-fold rotational symmetry in the iron plane. This phase may arise from orbital ordering, spin fluctuations, or hidden magnetic quadrupolar order. Here we use inelastic neutron scattering on a mosaic of single crystals of FeSe detwinned by mounting on a BaFe2As2 substrate to demonstrate that spin excitations are most intense at the antiferromagnetic wave vectors QAF = (1, 0) at low energies E = 6-11 meV in the normal state. This two-fold (C2) anisotropy is reduced at lower energies 3-5 meV, indicating a gapped four-fold (C4) mode. In the superconducting state, however, the strong nematic anisotropy is again reflected in the spin resonance (E = 3.7 meV) at QAF with incommensurate scattering around 5-6 meV. Our results highlight the extreme electronic anisotropy of the nematic phase of FeSe and are consistent with a highly anisotropic superconducting gap driven by spin fluctuations.
accepted for Nature Materials
References in corpus (10)
- Strong electronic correlations from Hund's coupling
- Evidence for an electron nematic phase transition in underdoped iron pnictide superconductors
- The Structural Phase Transition in FeSe (Fe1+dSe)
- Orbital-driven nematicity in FeSe
- Origin of the tetragonal-to-orthorhombic (nematic) phase transition in FeSe: a combined thermodynamic and NMR study
- The key ingredients of the electronic structure of FeSe
- Nematic spin correlations in the tetragonal state of uniaxial strained BaFe2-xNixAs2
- Anisotropic itinerant magnetism and spin fluctuations in BaFe2As2: A neutron scattering study
- Disorder-induced freezing of dynamical spin fluctuations in underdoped cuprates
- Fermi surface, pressure-induced antiferromagnetic order, and superconductivity in FeSe
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- Orbital-selective spin waves in detwinned NaFeAs
- Inter-orbital nematicity and the origin of a single electron Fermi pocket in FeSe
- Spin fluctuation anisotropy as a probe of orbital-selective hole-electron quasiparticle excitations in detwinned Ba(Fe1-xCox)2As2
- Frustrated magnetic interactions in FeSe
- Lattice dynamics in FeSe via inelastic x-ray scattering and first-principles calculations
- Magnetic-Field-Induced Spin Nematicity in FeSe1-xSx and FeSe1-yTey Superconductor Systems
- Theory of spin-excitation anisotropy in the nematic phase of FeSe obtained from RIXS measurements
- Quasi-one-dimensional spin excitations in the iron pnictide NaFeCuAs